Field
Exemplary embodiments relate to a touch sensor device. More particularly, the present disclosure relates to a flexible touch sensor device.
Discussion of the Background
An electronic device such as a liquid crystal display (LCD), an organic light emitting diode display (OLED display), and an electrophoretic display may include a touch sensing function such that it is capable of user interaction. A touch sensing function determines whether a user's finger, or some other touch instrument, touches a screen, and the touch position information thereof, by sensing a change of pressure, light, etc., that occurs on a screen in the display device when the user's finger or a touch pen contacts the screen to write a character or to draw a picture.
The touch sensing function of many types of electronic devices may be realized through a touch sensor. The touch sensor may be classified into various types such as a resistive type, a capacitive type, an electro-magnetic (EM) type, and an optical type.
For example, the capacitive touch sensor includes a sensing capacitor formed by a sensing electrode which may transfer a sensing signal, and senses a change in capacitance of the sensing capacitor generated when a conductor such as a finger approaches the touch sensor to determine existence of a touch, a touch position, and the like. The capacitive touch sensor may include a plurality of touch electrodes disposed in a touch sensing region sensing the touch and touch wires connected to the touch electrodes. The touch wires may transmit a sensing input signal to the touch electrode and transmit a sensing output signal of the touch electrode generated depending on the touch to a touch driver.
The touch sensor may be installed in the display device (an in-cell type), formed on an outer surface of the display device (an on-cell type), or attached via a separate touch sensor panel to the display device (an add-on cell type). Particularly, in a case of a flexible display device, an add-on cell type may be used by adhering a film in which the touch sensor is formed on to the display panel or by forming and adhering a separate touch sensor device having a plate shape on the display panel.
When producing various electronic devices having such display devices, the touch sensor device uses a glass substrate that is heavy and easily damaged. Accordingly, this limits its portability and implementation of large-scale screen displays. However, recently, a flexible electronic device which is light, impact-resistant, and uses a plastic substrate having high flexibility, such as polyamide (PI), has been actively developed. In this case, the flexible touch sensor device may include a portion that is bendable, foldable, rollable, stretchable in at least one direction, or is elastic and can be deformed.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.